Which level transmitter should be chosen?
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If the level of a paste-like liquid is to be measured, its density changes due to stirring inside the tank; which type of level gauge should be used?
I’d venture to guess that floats aren’t suitable (due to density changes), nor are double flanges (also due to density changes). It seems that a contactless approach would be more appropriate, such as using radar； For on-site indicators, choose glass plates; or select magnetic flap level gauges depending on density, pressure, and temperature conditions.
The Rosemount radar level gauges will do; the 3300 series, 5400 series, and 5600 series – choose according to the operating conditions
Using a side-mounted radar or ultrasonic level gauge
The simplest and cheapest option: glass mirrors, straight forward.
Due to mixing, neither radar nor ultrasonic level gauges can be used; the density cannot be determined, and level gauges based on the differential pressure principle are also not applicable. A radioactive level gauge should be used. This post was last edited by XJTZWKDPJ on 2008-1-6 18:21]
A weight gauge can be installed to convert the liquid level, which makes it more accurate.
Radar with waveguides can be used; installation is a bit more complicated as it is necessary to avoid the stirrer. What is the liquid temperature? A weighing device is to be installed; I’m not sure if it’s easy to install. The weighing device can also be used to convert the liquid level into a value that indicates density.
Using guided-wave radar, or radio frequency sonar, should work
Glass mirrors don’t work; the viscous liquid doesn’t flow easily.
Ultrasonic waves and radar can be used; today’s instruments are intelligent, and it is possible to configure them so that they automatically account for the effects of noise when calculating the level of liquid (whether due to mixing or circulation)
A radar is used to suppress the effect of stirring in the spectrum.
Is the dynamic viscosity very high? Consider using the external-type level gauge produced by Xi’an Dinghua Electronics; it measures based on the principle of minor vibrations in the liquid. When using radio frequency sodium guide technology, the issue of material presence needs to be taken into account.
If it is not for measurement but only for monitoring or control, as long as the density change is not too large, differential pressure measurement remains the most reliable method.
You must be mistaken... A radar level gauge can also be used while stirring... but it needs to be used through a connecting pipe for measurement... In this way, the impact caused by stirring is minimal
It is recommended to use a flush diaphragm pressure transmitter for measurement, which converts the output pressure signal into a level signal; it should be installed on the side at the bottom.
A radar level gauge or an ultrasonic level gauge should be used; you can consult the manufacturer for advice.
Knowing there are tigers in the mountains, one still chooses to tease them. Tell me exactly by how much the density changes – the fluctuations in the density of wastewater at wastewater treatment plants have never exceeded ±2%; cases where it changes from 1 to 1.5 are actually quite rare! For status monitoring, the signal shouldn’t fluctuate randomly or invert its polarity; stability of the signal is what’s essential. . . When the density variation is small, the median value can be used to ignore errors; when the variation is large, compensation is achieved through time-based or real-time density tracking. The technology is constantly evolving – today, static pressure methods involve using two or three sensors together, and there are already mature technologies and products available for this purpose. These systems do not rely on DCSs, PLCs, or other computers to carry out the calculations; instead, they process the measured values directly into electrical signals or digital values right at the source. Technology continues to advance, opening up new possibilities. . . Early static pressure methods used air-blown non-contact level gauges, while today gas-collecting pressure-guided non-contact level gauges have emerged as a competitive alternative. The advantages of gas-collecting pressure guidance are simplicity, safety, stability, precision, no dead zone, and lower cost. (Illustration omitted.) . . . . . . . . . . . ）
Magnetostrictive level gauges are preferable; they can provide local display as well as enable remote transmission to a DCS